Chloe Menderson is allergic to peanuts. A new study is aiming to desensitize people allergic to peanuts through a patch containing a peanut protein. / H. Darr Beiser, USA TODAY

by Kimberly Railey, USA TODAY

by Kimberly Railey, USA TODAY

Chloe Menderson's purse is always stocked with two items: Benadryl and an EpiPen.

For the Washington, D.C., native, those products are her only defense against a peanut allergy that poses a constant risk to her health.

"It takes one time forgetting to ask at a restaurant if there are peanuts in your meal to be in danger," said Menderson, 20. "You might ask every day of your life and then just not remember one day."

A peanut allergy study that's underway could help eliminate that risk. The research aims to desensitize people allergic to peanuts using a patch containing a peanut protein. The study, sponsored by French bio-pharmaceutical firm DBV Technologies, is being conducted in 24 centers worldwide.

Currently, there is no method, other than avoidance, to combat the condition. The allergy's symptoms can range from a minor irritation to a life-threatening reaction.

About 3 million Americans, or 1% of the general population, have a nut allergy, said Marshall Plaut, chief of food allergy, atopic dermatitis and allergic mechanisms at the National Institute of Allergy and Infectious Diseases.

That condition remains the greatest concern among clinicians who treat patients with food allergies, he said.

"It's the one associated with the highest rate of life-threatening allergic reactions and even death," Plaut said.

Enrollment for the study was completed this July, and the data are expected to be fully collected by July 2014.

Although the results could have far-reaching implications, it will take a few years to determine whether the patch is effective, said Amal Assa'ad, the primary investigator of the study at Cincinnati Children's Hospital Medical Center.

The study's ultimate goal is to make people with a peanut allergy tolerant of peanuts, even if they were to stop wearing the patch, Assa'ad said.

"If we achieve that, and with safety, it will have a really big impact," she said.

In recent years, studies to treat peanut allergies have aimed to desensitize participants to peanuts through under-the-tongue or oral therapy.

Although the treatments have been effective for some people, others have experienced side effects, including stomach pain and anaphylaxis, a life-threatening allergic reaction, said Scott Sicherer, a fellow at the American Academy of Allergy, Asthma and Immunology.

"The hope is that, by putting peanut on the surface of the skin, there will be few side effects," he said.

Compared with other food allergies, peanut allergies are more severe and persistent, Sicherer said. The allergy may also be growing more common because it has been reported in more children over the years, he said.

For many with nut allergies, the issue becomes easier to handle with age.

Scott Trahan, 18, said he hasn't had to check as many food ingredients as he has gotten older because he knows the types of foods that are safe to eat. Although he said he is careful about his allergy, he would like to see a treatment.

"If somebody could stop it, that would be one less inconvenience," he said.

In elementary and middle school, Trahan ate his lunch at a peanut-free table in the cafeteria, an option available at many schools, said Dianne Pratt-Heavner, a spokeswoman for the School Nutrition Association.

Still, there is always a chance of coming into contact with peanuts, for both children and adults. That possibility can cause anxiety and fear for those with the allergy, said Wayne Shreffler, the study's site investigator at Massachusetts General Hospital.

Although it's too early to tell whether the patch will be effective, Shreffler said any safe and credible treatment should be tested.

"There are a handful of really bad reactions and, if we can prevent them, that's huge," he said.